Catch can setups

[russyb]

It's the age old topic of catch cans

 

First up I'd like to run a full ventilation breather system ie drill out pcv valve on drivers side and from passenger side from rear of engine but....

All I can find is FI information on this full system is there some reason not to do this with a n/a car before I go ahead as most people who run naturally aspirated de's seem to just do driverside catch can setup.

 

Any advice would be great as the way I see it is its pointless to do just one side of crankcase..

 

Thanks in advance

[Tricky-Ricky]

so you want to do away with the PCV system? why? its very beneficial to ring and oil seals, just run the idle/low load side (plenum) to a sealed and baffled catch can and back to the plenum, this will eliminate pretty much all of the oil that collects in the plenum low points, the full throttle/load side is best left as is, but if you feel the need you can also add a catch can to this.

 

A lot of info here, http://www.350z-uk.c...n/#entry1349925

Edited May 15, 2016 by Tricky-Ricky

[Ekona]

^^^ Absolutely that. Leave the PCV in.

[russyb]

I understand leaving the pcv valve in and just running a sealed catch can between pcv valve and plenum return but what about the breather at the back that returns into the intake ?

Edited May 15, 2016 by russyb

[russyb]

Kinda like doing half a job ? Is there not some way to incorporate the 2 breathers into one catch can without removing the pcv valve?

Edited May 15, 2016 by russyb

[Tricky-Ricky]

Did you read the info in the link? just what is your reason for changing the system?

You cannot mix the plenum side which is closed with the open intake side as this will result in bad idle due to unmetered air being drawn in and affecting idle and higher loads, so you will literally be creating an air leak.

[russyb]

yes I did...

 

but I want to reduce oil residue inside the plenum galleys but also in the intake tract so just running the "usual" setup is not good enough imo

 

but from what I gather best/safe way is 2 sealed catch cans to avoid unmetered air

[Tricky-Ricky]

Yes two sealed cans are the best option if you feel you need two, but as the low load side is the one that generates the most oil vapor due to the high vacuum at idle, most people just use one catch can on this, believe it or not if you don't bother with the high load side you wont see any further oil reside in the throttle body, as its gets draw from the plenum by reversion, so one can is sufficient.

[russyb]

exactly the info I was looking for thanks ricky